Pioneering healthcare with soft robotic devices: A review

Abstract

Recent advancements in soft robotics have been emerging as an exciting paradigm in engineering due to their inherent compliance, safe human interaction, and ease of adaptation with wearable electronics. Soft robotic devices have the potential to provide innovative solutions and expand the horizons of possibilities for biomedical applications by bringing robots closer to natural creatures. In this review, we survey several promising soft robot technologies, including flexible fluidic actuators, shape memory alloys, cable-driven mechanisms, magnetically driven mechanisms, and soft sensors. Selected applications of soft robotic devices as medical devices are discussed, such as surgical intervention, soft implants, rehabilitation and assistive devices, soft robotic exosuits, and prosthetics. We focus on how soft robotics can improve the effectiveness, safety and patient experience for each use case, and highlight current research and clinical challenges, such as biocompatibility, long-term stability, and durability. Finally, we discuss potential directions and approaches to address these challenges for soft robotic devices to move toward real clinical translations in the future.

Keywords: implants; prosthetics; rehabilitations; soft robotic devices; soft sensors; surgical interventions; wearables.

FIGURE 1

Promising soft actuators for biomedical applications include (A) fluid‐driven soft actuators, (B) vacuum‐driven soft actuators, (C) magnetically driven soft actuators, (D) cable‐driven soft actuators, and (E) shape memory alloys.

FIGURE 2

(A) Flexible self‐sensing actuator with electronic skin, providing an integrated function in both tactile sensing and haptic feedback. Reproduced under terms of the CC‐BY license. Copyright 2022, The Authors, published by the American Association for the Advancement of Science. (B) Hydrogel‐based ionic skin (iSkin) capable of strain sensing. Reproduced with permission. Copyright 2021, John Wiley & Sons. (C) Inkjet‐printed soft resistive pressure sensor patch. Reproduced with permission. Copyright 2020, John Wiley & Sons. (D) Customizable silicone‐textile composite capacitive strain sensors. Reproduced with permission. Copyright 2017, John Wiley & Sons. (E) Eco‐Gr ink for smart socks with Na+ sensor and reference electrodes. Reproduced with permission. Copyright 2022, American Chemical Society. (F) Implantable soft platforms with printed nanomaterial‐based arterial stiffness sensors. Reproduced with permission. Copyright 2022, Elsevier. (G) Implantable soft device incorporated into a Langendorff‐perfused rabbit heart. Reproduced with permission. Copyright 2015, John Wiley and Sons. (H) Flexible and implantable polyimide aptamer‐field‐effect transistor biosensors. Reproduced with permission. Copyright 2022, American Chemical Society. (I) Fully implantable soft strain sensor for continuous heart‐volume monitoring. Reproduced with permission. Copyright 2020, John Wiley & Sons.

FIGURE 3

Stiffness control mechanism. (A) Active jamming. (B) Passive jamming. (C) layer jamming. Reproduced with permission. Copyright 2020, John Wiley and Sons.

FIGURE 4

(A) Intravascular retrieval catheter prototype. Reproduced under terms of the CC‐BY license. Copyright 2018, The Authors, published by John Wiley and Sons. (B) Origami‐based soft robotic actuator for upper gastrointestinal endoscopic applications. Reproduced under terms of the CC‐BY license. Copyright 2021, The Authors, published by Frontiers. (C) Soft robotic manipulator for intraoperative MRI‐guided transoral laser microsurgery. Reproduced with permission. Copyright 2021, The Authors, published by American Association for the Advancement of Science. (D) A soft pop‐up arm performs tissue counter‐traction during an ex‐vivo test on a porcine stomach. Reproduced with permission. Copyright 2017, John Wiley and Sons. (E) Soft pneumatic two‐degree‐of‐freedom steerable catheter. Reproduced under terms of the CC‐BY license. Copyright 2021, The Authors, published by Frontiers.

FIGURE 5

(A) Wearable exoskeleton for elbow medical rehabilitation with shape memory alloy actuators. Reproduced under terms of the CC‐BY license. Copyright 2017, The Authors, published by Hindawi. (B) System Components for soft‐inflatable exosuits. Reproduced under terms of the CC‐BY license. Copyright 2018, The Authors, published by Frontiers. (C) Soft robotic exosuit to assist the paretic ankle's gait functions after stroke. Reproduced with permission. Copyright 2017, The Authors, published by American Association for the Advancement of Science. (D) Wearable soft robotic exoskeleton for hip flexion rehabilitation. Reproduced under terms of the CC‐BY license. Copyright 2022, The Authors, published by Frontiers. (E) 3D‐printed soft robotic prosthetic hand with multi‐articulating capabilities. Reproduced under terms of the CC‐BY license. Copyright 2020, The Authors, published by PLOS. (F) SoftHand Pro system. Reproduced under terms of the CC‐BY license. Copyright 2021, The Authors, published by Springer Nature.